抗胸腺细胞血清性肾炎模型大鼠肾小球中C5b-9的沉积及NO、TNFα含量分析

目的: 探讨抗胸腺细胞血清性肾炎(ATSN)大鼠肾小球内C5b-9复合物的沉积与某些炎症介质和细胞因子如:一氧化氮(NO)和肿瘤坏死因子α(TNFα)的含量情况。 方法: 大鼠一次性静脉注射抗胸腺细胞抗血清(ATS)建立ATSN模型,定期对ATSN大鼠肾小球中的补体C5b-9复合物进行免疫组化染色定位、显微图像扫描半定量分析;并对有C5b-9包绕的肾小球系膜细胞(MC)进行计数。测定ATSN大鼠肾中诱生型NO合酶(iNOS) mRNA的表达、尿液中NO的代谢产物(NO^-₂／NO^-₃)及TNFα的排泄量。 结果: ATSN模型大鼠肾小球MC先溶解坏死后继发增生,病变早期(溶解时相)补体C5b-9复合物主要定位于肾小球系膜区及MC表面;随着病程的进展,被C5b-9包绕的MC逐渐减少, 病程初期ATSN大鼠肾小球MC有明显的 iNOS mRNA表达, 尿液中NO^-₂／NO^-₃ 和TNFα的排泄量也明显增加。在ATSN病变的增生阶段(一般7 d后),上述指标的变化逐渐趋缓。 结论: ATSN模型大鼠肾小球中MC逐渐溶解与补体C5b-9沉积及NO和TNFα的合成与释放有一定关系。     

抗C5b-9复合物抗血清对大鼠ATS性肾炎病变的抑制作用

给大鼠注射抗胸腺细胞血精（ATS）复制系膜增生性肾小球肾炎即ATS性性肾炎（ATSN）模型。同时应用兔抗大鼠补体C5b-9复合物抗血清进行处理,然后定期观察各组大鼠24h尿蛋白总量、肾小球内细胞总数、增殖细胞核抗原（PCNA）、a-平滑肌肌动蛋白（a-SMA）的表达及肾小球内C5b-9复合物的沉积情况。结果发现,用C5b-9抗血清处理的ATSN组上述各项指标均较未用C5b-9抗血清处理的ATSN组低。提示：抗鼠C5b-9复合物抗血清对大鼠ATSN病变有抑制作用。     

人补体C5b~9复合物对大鼠肾系膜 细胞一氧化氮生成的影响

目的:探讨人补体 C_5b~9复合物对大鼠肾小球系膜细胞(MC)合成一氧化氮(NO)的影响。方法:首先提取人补体C_5b~9复合物,同时培养出大鼠肾小球MC。然后用C_5b~9复合物刺激MC,观察刺激后6 h、24 h、和48 h培养上清液中NO代谢产物-硝酸根(NO₃^-)和亚硝酸根(NO₂^-)量的变化,并测定刺激后24 h、48 h时MC内环鸟苷酸(cGMP)的水平。结果:用人C_5b~9复合物刺激大鼠MC后可致培养上清中NO₃^-/NO₂^-含量增加,细胞内cGMP水平上升。NO合成增多能够被NO合酶(NOS)抑制剂—─-N^G-硝基-L-精氨酸甲基酯(L-NAME)所抑制。结论:人C_5b~9复合物能够增加大鼠肾MC 的NO合成。     

补体C5b-9复合物刺激大鼠肾小球系膜细胞合成NO的机制探讨

目的:探讨人C5b-9复合物刺激大鼠肾小球系膜细胞(MC)合成一氧化氮(NO)的机制。方法:用人C5b-9复合物刺激培养的大鼠肾小球MC诱生肿瘤坏死因子α(TNFα)和白细胞介素1β(IL-1β),并用抗TNFα或抗IL-1β单克隆抗体进行处理。在上述基础上,分析处理3 h、6 h及24 h时与NO升高有关的某些指标的变化。结果:经C5b-9复合物刺激6、24 h后的MC(C5b-9组)产生TNFα明显高于对照组,并能被TNFα单抗逆转。用C5b-9复合物刺激MC未见IL-1β的产生。另用C5b-9刺激3 h时可见MC表达iNOS mRNA,而在刺激6 h和24 h时,MCiNOSmRNA表达,MC内cGMP含量及培养上清液中NO³_-/NO²_-含量均显著高于对照组。不过,C5b-9刺激时加用TNFα单抗处理,这些指标在6 h、24 h时均较C5b-9组低。结论:C5b-9复合物早期(3 h)能诱导MC表达iNOS mRNA,而6h后NO的升高则与MC释放的TNFα作用有关。     

一氧化氮在实验性NIDDM大鼠心肌病变中的变化

目的:用非胰岛素依赖型糖尿病(NIDDM)模型,研究一氧化氮(NO)、构建型一氧化氮合酶(cNOS)与NIDDM早期心肌病关系。方法:给大鼠尾静脉注射小剂量链尿佐菌素,使大鼠糖耐量异常,然后加喂高热量食物,引起大鼠肥胖,饲养8周,可形成类似NIDDM模型。观察实验性NIDDM大鼠心肌超微结构、心肌NO产物NO₂^-/NO₃^-、cNOS表达的变化。结果:①透射电镜观察发现,NIDDM大鼠心肌有超微结构改变,例如:线粒体肿胀、心肌闰盘间隙增宽。②NIDDM大鼠心肌组织NO₂^-/NO₃^-水平显著低于正常对照大鼠(P＜0.01),L-精氨酸组心肌组织NO₂^-/NO₃^-显著高于NIDDM组(P＜0.01)。③NIDDM大鼠心肌组织cNOSmRNA表达显著低于正常对照大鼠(P＜0.01)。结论:NIDDM早期存在心肌病变,NO与其发生机制有关,L-精氨酸对NIDDM大鼠心肌病有一定的防治作用。     

大鼠肺纤维化形成过程中肺内一氧化氮代谢的动态变化

目的:观察大鼠肺纤维化过程中肺内一氧化氮代谢的动态变化及其与肺纤维化形成的关系。方法:气管内一次性滴注平阳霉素(5mL/kg),观察注后7、14、21、30d和70d组大鼠肺组织羟脯氨酸含量,出、入肺血NO₂^-/NO₃^-含量以及14d组肺泡巨噬细胞培养上清液中NO₂^-/NO₃^-含量和肺间质诱导型一氧化氮合酶(iNOS)免疫组化阳性细胞数量的变化。结果:7d组大鼠肺组织羟脯氨酸含量与对照组比无明显差异,14d组高于对照组(P＜0.05),21d组、30d组和70d组更为明显(均P＜0.01)。7d组、14d组出肺血NO₂^-/NO₃^-含量明显高于对照组(均P＜0.01),入肺血NO₂^-/NO₃^-含量明显低于对照组(均P＜0.01),21d组出肺血NO₂^-/NO₃^-含量的变化无明显差异(P＞0.05),入肺血仍较低(P＜0.01),30d组和70d组出、入肺血NO₂^-/NO₃^-含量与对照组无明显差异(P＞0.05)。14d组大鼠肺泡巨噬细胞培养上清液中NO₂^-/NO₃^-含量明显高于对照组(P＜0.01)。14d组大鼠肺间质iNOS免疫组化阳性细胞增多。结论:大鼠肺纤维化形成过程中,先有肺内NO生成增多,后出现肺纤维化;在肺纤维化形成后,肺内NO趋向恢复。肺内NO增多与肺泡巨噬细胞释放NO能力增加、肺内iNOS的增多有关。肺内NO的大量生成可能是促使肺纤维化形成的因素之一。     

心通胶囊对心肌缺血大鼠心室肌亚硝酸盐和cGMP含量的影响

目的:探讨心通胶囊对实验性大鼠心肌缺血的预防效果及其与一氧化氮形成的相关机制。方法:应用垂体后叶素致大鼠急性心肌缺血模型,以心电图上ST段的抬高作为心肌缺血的指标。测定大鼠心肌缺血心室肌组织一氧化氮(NO)代谢产物(NO₂^-/NO₃^-)和cGMP含量。结果:急性心肌缺血组大鼠的心室肌组织NO₂^-/NO₃^-和cGMP含量分别为(486±59)nmol/gprotein和(0.38±0.08)nmol/gprotein,明显低于正常对照组大鼠的NO₂^-/NO₃^-和cGMP含量,有显著差异(P＜0.01);急性心肌缺血前使用心通胶囊组的心室肌组织NO₂^-/NO₃^-和cGMP含量为(845±105)nmol/gprotein和(0.51±0.10)nmol/gprotein明显高于缺血组(P＜0.01)。与正常组比较,缺血组的心电图ST段抬高明显抬高(P＜0.05);心肌缺血前使用心通胶囊,可使心肌缺血得以改善。结论:心通胶囊提高急性心肌缺血大鼠心室肌组织的NO含量,进而使cGMP含量升高,达到改善心肌缺血的作用。     

吸烟大鼠一氧化氮合酶和一氧化氮的变化

目的:观察吸烟对大鼠肺组织iNOS、eNOSmRNA和蛋白表达以及支气管肺泡灌洗液(BALF)中NO的影响, 探讨不同类型的NOS在吸烟所致慢性气道炎症中的作用。方法:选用Wistar大鼠80只随机分为对照组, 被动吸烟组, iNOS抑制剂L-NIL干预组及NOS抑制剂L-NAME干预组。用免疫组化法检测iNOS及eNOS的蛋白表达, 用RT-PCR检测iNOS及eNOSmRNA的表达, 用Griess法测定BALF中的NO^-₂/NO^-₃含量。结果:吸烟大鼠肺组织中iNOSmRNA及其蛋白表达增加, eNOSmRNA及蛋白表达下降, BALF中细胞总数及NO^-₂/NO^-₃显著增加(P＜0.05)。在体实验发现, L-NIL使BALF中细胞总数及NO^-₂/NO^-₃下降(P＜0.05);L-NAME对BALF中细胞总数及NO^-₂/NO^-₃无显著影响(P＞0.05)。结论:吸烟大鼠肺组织iNOSmRNA和蛋白表达增加, eNOSmRNA和蛋白表达减少。活化的iNOS产生大量NO促进炎症发展。     

NF-κB抑制剂（PDTC）对大鼠抗胸腺细胞血清性肾炎系膜细胞凋亡、坏死及增生的影响

目的:研究吡咯二硫氨基甲酸脂(PDTC)作为NF-κB核转录因子特异性抑制剂对大鼠系膜增生性肾炎,即抗胸腺细胞血清性肾炎(ATSN)系膜细胞(MC)凋亡、坏死及增生病变的影响。方法:利用兔抗大鼠胸腺细胞抗血清(ATS)复制大鼠ATSN模型,并将大鼠设为3组,即ATSN模型组、ATSN PDTC处理组和正常对照组。实验40min、24h和7d分别取各组大鼠肾皮质切片用末端转移酶介导的dUTP缺口末端标记(TUNEL)技术和光镜、电镜、免疫组化方法检查其肾小球内NF-κBp65的表达和MC凋亡、坏死及增生病变。结果:ATSN模型组实验40min时肾小球内NF-κBp65即开始表达,与对照组之间有显著差别(P<0.01),24h表达进一步增多,第7d时达到较高水平。而ATSN PDTC处理组7d时,不仅肾内NF-κBp65的表达明显低于ATSN模型组,且肾小球MC的增生及细胞外基质(ECM)的分泌也低于ATSN模型组,但用PDTC处理对ATSN大鼠其早期(40min及24h)MC的病变无抑制效应。结论:NF-κB特异性抑制剂PDTC对ATSN大鼠的肾小球继发增生病变有抑制作用。     

银杏叶提取物对糖尿病大鼠睾丸损伤的作用

目的:研究银杏叶提取物(GBE)对糖尿病所致的睾丸损伤的作用及其机制。方法:用光镜及透射电镜观察链脲佐菌素(STZ)诱导的糖尿病1个月大鼠睾丸的形态学改变,并测定睾丸组织丙二醛(MDA)、NO产物NO₂^-/NO₃^-的含量及超氧化物歧化酶(SOD)、一氧化氮合酶(NOS)的活性。 结果:①糖尿病大鼠睾丸组织光镜下主要表现为睾丸曲细精管萎缩、变形及生精上皮脱落,透射电镜下主要见到支持细胞浆内内质网扩张、脂滴空泡形成,溶酶体明显减少,银杏叶组大鼠睾丸组织光镜、透射电镜下上述病变明显改善。②睾丸组织的MDA、NO₂^-/NO₃^-含量及tNOS和iNOS活性银杏叶组低于糖尿病组,SOD活性银杏叶组高于糖尿病组。 结论:GBE对糖尿病所致的睾丸损伤有明显的保护作用,其作用机制与提高SOD活力减少MDA产生,抑制iNOS活力减少NO产生有密切关系。     

补体C5b-9复合物诱导大鼠肾系膜细胞iNOS mRNA表达的实验研究

观察人血清补体C5b 9复合物对大鼠肾小球系膜细胞 (MC)表达诱生性一氧化氮合酶 (iNOS)mRNA的影响。方法 :首先提取人血清补体C5b 9复合物 ,然后用人C5b 9复合物刺激培养的大鼠MC ,检测MC在受C5b 9复合物刺激后3、6、2 4和 48h时iNOSmRNA的表达情况。同时检测其培养上清液中一氧化氮 (NO)代谢产物———硝酸根 (NO3- )和亚硝酸根(NO2- )含量的变化。结果 :用人C5b 9复合物刺激培养大鼠的肾MC能使其表达iNOSmRNA ,培养上清液中NO3- NO2- 含量也明显升高。人C5b 9复合物对MC的刺激作用能部分被相应的抗人C5b 9复合物抗体和RNA合成抑制剂———放线菌素D所抑制。结论 :人补体C5b 9复合物具有刺激大鼠肾MC合成NO的作用。     

4种肾炎模型大鼠尿液中补体C5b-9复合物排泄的比较研究

目的: 探讨不同类型的免疫复合物肾炎大鼠尿液中补体C5b-9复合物检出的意义。方法: 复制大鼠被动型Heymann肾炎(PHN)、抗胸腺细胞血清性肾炎(ATSN)、抗肾小球基底膜性肾炎(AGBMN)及慢性血清病肾炎(CSDN)4种动物模型。用双抗体夹心ELISA法定期检测各种肾炎大鼠血液及尿液中补体C5b-9的含量,同时观察大鼠肾小球中C5b-9的沉积情况。结果: 4种肾炎模型鼠血浆C5b-9复合物均见上升,肾小球内也有C5b-9复合物的沉积,但尿液中C5b-9含量升高仅见于罹患PHN的大鼠。此外,尿液中C5b-9复合物的升高先于PHN大鼠尿蛋白的升高。结论: 尿液中C5b-9复合物的检测可作为PHN早期诊断和鉴别诊断的一种敏感性较高的免疫学指标。     

Sublytic C5b-9 complexes induce proliferative changes of glomerular mesangial cells in rat Thy-1 nephritis through TRAF6-mediated PI3K-dependent Akt1 activation

The proliferation of glomerular mesangial cells (GMCs) and secretion of extracellular matrix (ECM) in rat Thy-1 nephritis (Thy-1N), resembling human mesangioproliferative glomerulonephritis (MsPGN), have been studied for many years, but the mechanisms, especially the role of signalling pathway activation and its regulation in GMCs triggered by sublytic C5b-9 complexes in Thy-1N rats remain largely unclear. In the study, the proliferation of GMCs and production of ECM as well as the role of PI3K/Akt and its regulation, both in GMCs induced by sublytic C5b-9 (in vitro) and in the renal tissues of rats with Thy-1N (in vivo), were determined and the results revealed that GMCs proliferation and ECM secretion, both in vitro and in vivo, were notably increased, and that PI3K/Akt1 activation and its regulation, such as TNF receptor-associated factor 6 (TRAF6)-mediated Akt1 ubiquitination and PI3K-dependent Akt1 phosphorylation, were involved in the process of Thy-1N induction. On the other hand, silence of the TRAF6, PI3K or Akt1 genes could obviously diminish the proliferative damages and urinary protein secretion of Thy-1N rats. Together, these data implicated that sublytic C5b-9 complexes in Thy-1N rats could promote GMCs proliferation and ECM production through TRAF6-mediated PI3K-dependent Akt1 activation, in which the ubiquitination and phosphorylation of the Akt1 signal molecule played an important role in the initiation and development of the proliferative changes in the rats with Thy-1N.     

Urinary excretion of the C5b-9 membrane attack complex of complement is a marker of immune disease activity in autologous immune complex nephritis.

The urinary excretion of the C5b-9 membrane attack complex of complement correlates with glomerular deposition of antibody in the passive Heymann nephritis (PHN) model of membranous nephropathy (MN). To determine if this parameter can be correlated with antibody deposition in a model of MN induced by an autologous mechanism and thus more analogous to human MN, the relationship of urinary C5b-9 to ongoing glomerular immune complex formation late in autologous immune complex nephritis (AICN) was studied. Based on urinary C5b-9, the animals were divided into two groups at 12 weeks after induction of AICN, those with persistently high urinary C5b-9 excretion and those in whom urinary excretion of C5b-9 returned to undetectable levels. While all rats developed glomerular deposition of rat IgG and significant proteinuria, high C5b-9 excretors had greater proteinuria and prolonged positive staining for glomerular C3. When normal syngeneic kidneys were transplanted into rats (n = 3) from each group, only those with persistent C5b-9 excretion developed subepithelial immune deposits of rat IgG in the transplanted kidney. As in the PHN model of MN, proteinuria was dissociated widely from urinary C5b-9 excretion, glomerular C3 staining, and evidence of circulating antibody. Thus these findings demonstrate that urinary excretion of C5b-9 serves as an index of on-going immunologic disease activity in the AICN model of MN, while proteinuria does not.     

Localization of terminal complement components S-protein and SP-40,40 in renal biopsies

The terminal complement complex has been implicated in the development of glomerular injury in both experimental and, indirectly, in human glomerulonephritis. Recent data suggests that the terminal complement complex in human glomerulonephritis may be in the cytolytically inactive SC5b-9 form which also contains S-protein and a recently identified protein, SP-40,40. In this study renal biopsies were examined by immunofluorescence to determine the incidence and inter-relation of deposition of the SC5b-9 components C6, C9, S-protein and SP-40,40. All components of SC5b-9 were found in arteries and arterioles, along the tubular basement membrane and in areas of glomerulosclerosis in all biopsies. This deposition was sometimes associated with C3 but never immunoglobulin deposition and correlated with the degree of renal injury. In addition, in biopsies with glomerular deposition of immunoglobulin and C3, the SC5b-9, components co-localized with the immune deposits. Glomeruli without immune deposits or glomerulosclerosis contained none of the SC5b-9 components. The incidence and pattern of distribution of SP-40,40 was similar to that of S-protein, C6 and C9 in all of cases. These data confirm that the terminal complement complex in the kidney is, at least partly, in the SC5b-9 form both in the specific immune glomerular deposition and in the "non-specific" deposition in areas of renal injury. SP-40,40 is also found in the SC5b-9 complex in all forms of renal disease.     

Apoptosis of glomerular mesangial cells induced by sublytic C5b‐9 complexes in rats with Thy‐1 nephritis is dependent on Gadd45γ upregulation

The complement C5b‐9 complexes can result in cell apoptosis, but the mechanism of sublytic C5b‐9‐mediated glomerular mesangial cell (GMC) apoptosis in Thy‐1 nephritis (Thy‐1N) remains largely unclear. The Gadd45 gene is involved in the cellular response to DNA damage and can promote cell apoptosis. In this study, both Gadd45γ expression patterns and pathologic changes of renal tissue were examined in rat Thy‐1N. Both Gadd45γ expression and GMC apoptosis were significantly decreased in Thy‐1N rats upon the depletion of complement with cobra venom factor. Our in vitro studies showed that Gadd45γ over‐expression increased sublytic C5b‐9‐induced GMC apoptosis, while Gadd45γ gene knockdown by siRNA greatly reduced GMC apoptosis. Moreover, Gadd45γ gene silencing in vivo markedly inhibited the pathologic changes in the renal tissue of Thy‐1N rats. These data suggest that Gadd45γ gene expression is involved in regulating GMC apoptosis mediated by sublytic C5b‐9 in Thy‐1N.     

Immunohistochemical study of complement S protein (Vitronectin) in normal and diseased human kidneys: relationship to neoantigens of the C5b-9 terminal complex.

The localization of S protein (Vitronectin) antigen was studied by indirect immunofluorescence and immunoelectron microscopy in normal adult human kidneys and in biopsy specimens from patients with a wide range of renal diseases, and compared with that of neoantigens of the C5b-9 terminal complement complex. S protein antigen was diffusely present in arteriolar perimyocytic matrices, the glomerular basement membrane and mesangial matrix, and tubular basement membranes in the cortex of normal and diseased kidneys without superimposable staining for C5b-9 neoantigens. Cell remnants embedded in normal and sclerotic extracellular matrices expressed S protein antigen and also stained for C5b-9 neoantigens. Several lines of evidence suggested that S protein present in connective matrices most likely represents S protein or C5b-9 complexes trapped from the circulation. Glomerular immune deposits and arteriolar hyalin deposits which contained C5b-9 neoantigens also contained S protein antigen in the same location. In a few specimens from patients with membranous nephritis stage I and IgA nephropathy, immune deposits contained neither detectable C5b-9 neoantigens nor S protein. The observed strong co-staining of immune deposits for S-protein and C5b-9 caution against the generalization that C5b-9 within glomerular immune deposits represent membrane-bound cytolytic complement complexes.     

Glomerular C3c localization indicates ongoing immune deposit formation and complement activation in experimental glomerulonephritis.

In antibody-mediated glomerular disease, deposits of C3 (C3b) are common and are degraded by factor I to C3c and C3d. However, the kinetics of C3b degradation in glomerulonephritis have not been defined. To do this, we studied three models of complement-dependent glomerulonephritis with established C3 deposits (passive Heymann nephritis, cationized immunoglobulin G membranous nephropathy, and concanavalin A-anticoncanavalin A glomerulonephritis). C3b deposition was halted by administration of cobra venom factor, and the disappearance of C3c and C3d from glomeruli was measured with specific antibodies and quantitative fluorescence densitometry. Results showed that C3c deposits were reduced by over 85% within 24 hours in all three models. C3c clearance was unaffected by site or mechanism of deposit formation. C3d deposits persisted despite lack of ongoing complement activation. In passive Heymann nephritis when disease activity was monitored by urinary C5b-9 excretion, C3c was cleared in parallel with return of urine C5b-9 excretion to normal values. We conclude that glomerular deposits of C3c are cleared within 24 hours of cessation of complement activation. Positive staining for C3 utilizing antibody specific for the C3c portion documents recent complement activation usually reflecting new immune deposit formation.